Texas OPERATIONAL Ventilation Requirements - eQuest Related

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Gang:

I am trying to find where in the Texas Health and Safety Code where is says you must OPERATE ventilation in a certain manner, not just design a system to provide such ventilation. Tells me if i can reduce or eliminate exhaust air during certain times of the day (eQuest EEM).

California Title-24, Subchapter 3, Section 121.c.1 specifically states:

1. Times of occupancy. The minimum rate of outdoor air required by Section 121(b)2 shall be supplied to each
space at all times when the space is usually occupied.
EXCEPTION 1 to Section 121(c)1: Demand control ventilation. In intermittently occupied spaces that do not
have processes or operations that generate dusts, fumes, mists, vapors or gasses and are not provided with local
exhaust ventilation (such as indoor operation of internal combustion engines or areas designated for unvented
food service preparation), the rate of outdoor air may be reduced if the ventilation system serving the space is
controlled by a demand control ventilation device complying with Section 121(c)4.
EXCEPTION 2 to Section 121(c)1: Temporary reduction. The rate of outdoor air provided to a space may be
reduced below the level required by Section 121(b)2 for up to 5 minutes each hour if the average rate for each
hour is equal to or greater than the required ventilation rate.
NOTE: VAV must comply with Section 121(c)1 at minimum supply airflow.

I am trying to find a similar edict for the State of Texas.

Any takers?

John R. Aulbach, PE, CEM

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ashrae 62.1-2004 section 5.4 ventilation controls. mechanical
ventilation systems shall include controls, manual or automatic, that
enable the fan system to operate whenever the spaces served are
occupied. the system shall be designed to maintain the minimum outdoor
airflow as required by section 6 under any load condition. note: vav
systems with fixed outdoor air damper positions must comply with this
requirement at minimum airflow.

ashrae 62.1-2007 user's manual, page 5-11. user's manual example also
explains why the 'auto' setting for fan on a basic thermostat does not
meet the requirement to provide outdoor air when the spaces is occupied
- the fan will cycle off when setpoint is reached and no outdoor air
will be supplied until the next call for cooling & the fan comes back on.

Patrick J. O'Leary, Jr.'s picture
Joined: 2011-09-30
Reputation: 200

A quick search reveals that the State of Texas adopted the IECC 2009
code effective April 2011. This document may provide some directions
as to OA control.
http://www.seco.cpa.state.tx.us/tbec/comres.php

>> Christopher Jones, P.Eng.

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